There are many different designs used for the hands of the watch. Hands that are a dark navy in colour are called "blued steel" hands and are the result of super heating steel until the colour changes. This technique was first used by the famous watchmaker Abraham-Louis Breguet in the 19th century to help make the hands more legible.
Many watches have glow-in-the dark hands and hour markers. The substance used for this purpose has evolved over the years. Originally, Radium was used in the 1950's but was found to be highly radioactive and was replaced with a substance called Tritium. Tritium had much lower levels of radiotoxicity and was considered a much safer alternative to Radium. You can tell if a watch has Radium or Tritium markers because it will have the letter'T'or'R' printed on the dial, usually flanking the country of origin (ex. T-Swiss Made-T, or R-Swiss Made-R). Recently a new substance, Super-LumiNova®, has been introduced, which has no radioactive properties and is three times as bright as Tritium. It also does not discolour as Tritium does when it ages.